Otford Tunnel (Tunnel No. 7)

The Otford Tunnel is the grand tunnel, of all the six disused rail tunnels in the Helensburgh and surrounds area. None of the other five existing tunnels have more written about them than the Otford Tunnel. Technically it is the No.7 tunnel on the Illawarra line, measuring a whopping 1550m in length, more than double the length of any of the other five tunnels. The tunnel is dead straight right up until the Stanwell Park end where there is a short curve, on a steep 1 in 40 grade.

PERSONAL MEMORIES – In the 70’s, my aunty would often look after me when I was quite young. She owned a house in Station Road, Otford, and I remember vividly hearing the diesel trains with their heavy loads, thunder through Otford. Tractors would be busying in the approach to the northern portal of Otford Tunnel, as at this time, it was a busy mushroom farm. I clearly remember the smell of mushroom compost and used to watch the tractor turn the compost to see masses of steam rising from it. In the late 70’s my aunty met with one of the workers from the mushroom farm and a romance blossomed. He lived in the house which is located on the northern side of the school boundary next to the schools field, and left of the entrance road to the then mushroom farm.

Some time had passed and I remembered one afternoon going down to the mushroom farm with my cousin who was of similar age. We went into the northern portal of Otford Tunnel on the back of a tractor with my uncle, and goofed around in there while my newly related uncle did his job of farming mushrooms. I remember the smell of mushroom compost more than anything as the scent would emanate through the air and bathe the whole of Otford with its organic stench. I also remember many old wooden box crates piled on top of each other. They looked old, as the wood was that grey, weather beaten colour. The tractor used in the tunnel had really flat tyres and to my amazement and shock, I watched my cousin place his foot under the back tyre of the tractor. The expression on my face must have been of horror as my cousin just laughed at me. He said “try it”…”it doesn’t hurt”. Cautiously I did and I immediately wanted to pull away but kept my foot in the path of the tractor tyre. The tyre is coming closer and closer, I start to get nervous and it goes over my foot. A mass of pressure now starts to weigh on my foot but its soon over. “I did it” I yelled. I think we did it another 5 times after that. I have no idea what my uncle was thinking letting two children place their feet under a tractor tyre, but as I recall he didn’t say anything.
Years later I showed my Father a photo of the strange prawn looking tractor that has been discarded and abandoned in the Otford Tunnel. He told me that he remembers when it was in use, and that my uncle and his work mate used to fool around with that piece of machinery. I can’t remember it however… as my memories of the Mushroom Farm are few.

Another time I remember, was being woken very early in the morning as it was still dark. In thinking back, it must have been around 2-3am, and my uncle had a delivery of mushrooms to the Sydney Markets. The trip to the Markets was long and I think I must have slept most of the way as I can’t recall much other than a long drive in the dark. Upon arriving I remember the truck driving into a HUGE warehouse at night where there was loads of space and few people. I don’t remember much after that as I think I must have fallen asleep. A vivid memory it is and one that is etched into my mind. I must have been no more that 4 or 5 years old at the time.

A few years after this my aunty, uncle and two cousins packed up their belongings and moved north. Both houses are still intact and standing in Station Road, Otford today. Their appearance has altered greatly but they are still there. All access to the northern end of Otford Tunnel is completely blocked. A couple of houses have been built near and on the driveway leading down to the northern end of Otford Tunnel, and the area outside of the tunnel where the mushroom production existed is completely overgrown with weeds and lantana. UPDATE: November 2013. I visited the northern portal in late October and was pleased to see that a lot of lantana had been killed and removed. The portal is visible again and the local landcare group has done a marvellous job removing the thickets of weeds and lantana. The area just outside the tunnel where the blower system was housed (in later life, where the mushroom packing sheds were), the lantana has been thoroughly cleared. The alignment has been landscape by the Station Road residents. Although this is technically not their land, the residents have done a great job restoring the former rail corridor with green grass and willow trees for their enjoyment.

BRIEF HISTORY – Otford itself has a rich history and in the early days, grazing and farmlands in the valleys was common right up through to Lilyvale and beyond. The other areas in Otford were to be prized for their inhabitants of some of the best cedars in Australia supporting several mills at the time. A popular well known family in Otford around the 1860’s were the Gardiner’s who’s offspring included six sons and three daughters. Their property consisted of goats for milk, grapes for wine and the training of horses.

In the 1880’s the government decided that a rail link from Sydney to the Illawarra was needed as farming and mining warranted it. Gangers moved in the area starting at Westmacot (Waterfall) then Cawley and Camp Creek (Helensburgh) in 1884. By 1889 the 1st Helensburgh Railway Station opened sending its first train off to Sydney the following year. By 1885 the line had reached Otford and the gangers set up their camps to work on an engineering feat; the Otford Tunnel. During this time the township had the nickname of ‘Little Italy’ as most of the gangers on the tunnels construction were Italians. The rock removed to create the tunnel was an astounding 49,000+ cubic meters and the gangers would work in shifts to complete the tunnel. Five million bricks were made and used in the tunnels construction.

TUNNEL PROBLEMS – Soon after its construction, the Otford Tunnel became problematic. The Otford Tunnel and the Metropolitan Tunnel were becoming notorious for hot and suffocating conditions experienced by the crew of steam trains climbing to Waterfall. Combine this with larger, heavier trains, and increased traffic using the line, compounded the issues.

Many trains would have to roll back to Stanwell Park station after stalling or having both travellers and engine crew of the trains, choked, asphyxiated, and sometimes burnt, in the tunnel. The engine crews only option was to shut off the engine, engage the brakes and roll back to Stanwell Park. Engine crew would split the carriages and make several trips up to Waterfall then reattach the full load and continue on. Many a story has been circulated by passengers and crew recounting stories of their torture through the Otford Tunnel. Although a tablet system* was introduced making the passage between Stanwell Park and Otford safe, the massive 1 in 40 grade made it very steep and difficult for heavy steam trains heading north.
*Only one train was allowed on the section at a time making it safe. The driver would pick up the tablet from Stanwell Park Station and head to Otford Station. Trains behind him could not leave Stanwell Park until the first driver had relinquished the tablet at Otford. This would be relayed to Stanwell Park that the train had successfully passed through the tunnel and the next train could continue.

VENTILATION SHAFT – In 1891 the Minister for Public Works had accepted a tender from John McDonald to construct a ventilation shaft in the roof of the tunnel to aid in clearer and cleaner air. This was done approximately halfway into the tunnel at a depth of approximately 60m deep with the main vent shaft being 2m wide which expanded into the top of the tunnels roof forming a pretty impressive cone. This worked for a certain period of time but the problems of soot and smoke continued as time went by. Larger trains (double-headed and push-up locomotives), increased traffic with greater loads; compounded the problem. Other methods were needed to remedy this problem.

SOOT PROBLEMS CONTINUE (SOLUTIONS) – As the years went by, suggestions at the time (early 1900’s) consisted of a rope or cable to haul the trains through the tunnel, electrifying the line between Stanwell Park and Waterfall with a third rail being laid in the Otford Tunnel to provide the electrification as the roof had not enough clearance. Ideas that never came to be as plans for the deviation were in discussions and by 1908 the deviation was being re-surveyed to give a 1 in 80 grade. By 1909 another way to overcome the severe problems of soot and smoke were implemented. The installation of a massive blower system was initiated with a false portal being installed at the front of the original portal at the northern end. An engine room was constructed just outside the northern portal housing a massive gas engine, (later replaced with a steam engine). This would blow air through the tunnel south along the roof and walls clearing the tunnel of fumes and smoke in minutes. This remained in operation until the remaining section of the deviation works were completed in 1920. There was a delay in the completion of the deviation between Otford and Coalcliff due to the war, and full operations on the new deviation didn’t swing into action until October 1920. The blower fan was later purchased by the Lithgow Mine in 1923 and was overhauled and converted into an exhaust fan at the mine.

TUNNEL BLOWN UP, WWIIINVASION POLICY– After the Otford Tunnel was decommissioned on the 10th of October 1920, for years afterwards it became a nice walk for pedestrians as a shortcut between Stanwell Park and Otford. Especially as the train fair from Otford to Sydney was considerably cheaper than it was from the Stanwell Park Railway Station.
One of my favourite stories of the Otford Tunnel revolves around the rectangular concrete brace holding up part of the tunnel just inside the southern portal. Fears of a Japanese invasion were taken as a serious threat, and the government at the time put in place a national defence plan. Part of this plan was securing all beaches around Sydney, disabling the railway system, and blow up bridges and rail tunnels along the east the coast, (with the Sydney Harbour Bridge being the one exception). The ‘Scorched Earth Policy’ saw the Military ordering a test explosion in the Otford Tunnel, preventing intrusion of an advancing hostile enemy and making the spoils of war easy. The army exploded a demolition charge in the roof 30-odd metres in the southern end of the Otford Tunnel completely blocking access in 1942.

I recently got the chance to speak with John Oakes; (a life member of the Australian Railway Historical Society, and author of many fascinating books on Australia’s Railways). He mentions in his book ‘Sydney’s Forgotten Illawarra Railways‘, that during the centenary of the Otford tunnel (1988), a gentlemen was attending named Neil Langdon. Neil was an Australian ex-serviceman and was the person who placed the charge in Otford Tunnel and blew it up. John Oakes recounts that Neil apologised to the society for doing this.

In 2008 up on the Central Coast, Steve from the website, ‘All things Woy‘ took a bushwalk to the top of the Woy Woy Tunnel. There, he photographed a suspected wartime ammunitions dump directly above the tunnel, but was unable to obtain any further information about it. Eventually he made contact with Pete Dunn who managed to track down a mention of demolition plans for the Brooklyn area tunnels and bridges, (the Scorched Earth Policy) in the National Archive Records. This then led to another acquaintance; a geologist named John Byrne, who obtained some very interesting material about the Japanese Invasion. I mentioned this as it is worth a read if you’re interested in this history. Article can be found at: Woy Woy Tunnel demolition plan revealed.
The following image was obtained by the gentlemen mentioned above, from the National Archive Records. Interestingly, not only was the Otford Tunnel on the document, but also the Scarborough Tunnel (A.K.A Clifton Tunnel No.8), and the current Bald Hill Tunnel, marked as “New Otford Railway Tunnel” on the document.

AFTERLIFE – Years passed and water had banked up behind the fallen earth creating a dam. Hardly anyone could walk right through after the tunnel was blown in, although there are stories of some people being able to crawl through a small opening in the earthen heap, emerging at the Stanwell Park end during times of drought when not much water was present in the tunnel. During the early 60’s, mushroom farmers leased the tunnel to cultivate mushrooms. The 70’s saw the mushroom farmers clear the fallen debris from the explosion and erect a rectangular concrete brace which allowed passage once again, (although the tunnel was gated with locked doors on both ends). By the late 80’s the mushroom cultivators had vanished and the land was leased to another company which ended anyone entering the area. The late 80’s early 90’s several attempts by State Rail to restrict access to the tunnel, all have been vandalised and failed shortly thereafter.

In 1999 the State Rail Authority (RailCorp), deemed the tunnel unsafe due to erosion and past human actions.

In 2000-2001 the Sydney Water Corporation made plans to have a sewerage pipe routed through the tunnel to link Stanwell Park to the sewerage system. Presentations were made to the Heritage Council who were advised of several other proposals but had considerable costs involved. The proposal were:

a pipeline laid partly following Lawrence Hargrave Drive with two pumping stations required in restricted areas;

a new tunnel to the cost of $8 million;

construct a pipeline over Bald Hill with similarities to the 1st proposal with greater environmental impact.

The cost to use the disused Otford Tunnel was quoted in section 60 of their application as being in the range of $500,000.00 to $1,000,000.00. After consideration by the members of the Heritage Council the members agreed that the presentation by Sydney Water to have been poor and lacking in detail. After much debate and working out of finer details, the council approved the application with several conditions.

the pipe should be fixed to wall with non-ferrous fixings, preferably into the joints, and otherwise conform to Recommendation 1 of the Heritage Impact Statement (HIS);

further consideration be given to reducing the visual impact of the pipe;

the pipe should be buried at the south portal to conform to recommendation 4 of the HIS. The pipe is to be buried as far as possible in the tunnel without disturbing significant archaeology. The minimum length for the buried portion of the pipe within the tunnel, from the portal is 20 metres;

that the location of the SPS4 pumping station conform to recommendation 6 of the HIS, but the precise location, elevations, construction details and details of any associated equipment be subject to approval by the Director of the Heritage Office. The detailed plans are to include the relationship of the pumping stations and associated equipment to the curtilage boundary of the item and to significant archaeology like the track bed;

the pipe should remain buried from the south portal to SPS 4 pumping station and beyond it as in recommendations 5 and 7of the HIS;

the nominated excavation director must be present to monitor any excavation works and to record any archaeological features that are located. Significant relics should not be removed and should be retained in situ. The pipeline is to be diverted around relics if found;

the works will be supervised on site by a consultant/s experienced in the conservation of similar heritage items;

the repair works required to the tunnel, to enable the installation of the pipe, must be carried out prior to or in parallel with these works. The repair works will require a separate section 60 application where they are in excess of the Standard Exemptions. These repair works must include items 10, 12 & 15 of the Recommendations of the HIS described by Edward Higginbotham & Associates;

a Conservation Management Plan (CMP) should be prepared and endorsed by the Heritage Council prior to the repair works being carried out to inform the future management and interpretation of the heritage item. The CMP should include consideration for limited public access to the tunnel;

a Conservation Management Plan (CMP) should be prepared and endorsed by the Heritage Council prior to the repair works being carried out to inform the future management and interpretation of the heritage item. The CMP should include consideration for limited public access to the tunnel;

a photographic archival record shall be prepared including black and white prints and colour slides prior to the commencement of works. Copies are to be lodged with Wollongong Council and the NSW Heritage Office prior to the commencement of works;

a photographic archival record as described above shall be prepared of any significant fabric uncovered during the course of the works. Copies are to be lodged as described in i);

a photographic archival record as described above shall be prepared at the completion of the work. Copies are to be lodged as described above;

a Heritage Agreement must be signed by Sydney Water (as applicant for the work), the State Rail Authority (as owner of the heritage item) and the Minister for Urban Affairs and Planning to cover the conservation, adaptive re-use and maintenance of the heritage item;

the Heritage Council notes that as the proposal has the potential to improve visitor access to the tunnel a strategy that will facilitate safe public access and interpretation of the tunnel will be prepared to the satisfaction of the Heritage Council.

OTFORD TUNNEL TODAY – The last point has interesting implications from a rail and historic enthusiast point of view. I look forward to seeing what comes of it if anything. I remember reading a comment posted online from a surveyor who had passaged through the tunnel recently to survey it for the Water Board. I don’t think much has become of the proposal because as of October 2009, nothing has disturbed the growth of lantana and other weeds encroaching on the northern portal entrance of the Otford Tunnel, let alone the presence of a sewerage pipe construction. Nothing is in the tunnel except the remains of the mushroom cultivators machinery, at the entrance (northern end), and a piece of machinery [mentioned earlier], in the middle of the tunnel near the ventilation shaft.

Accessing the northern end of the Otford Tunnel is almost impossible if you don’t know how to access it. Access through the old driveway is now block as mentioned before, and western access is almost impossible. Cutting through the school is a commonly used access route but is fraught with danger such as lantana thick as aerosol cans and stinging nettle, not to mention the alignment floor is now a nice water reservoir. The false portal is still present although the whole portal can barely be seen because of weed infestation. Upon entry, you are immediately greeted with piles of rubbish abandoned by the mushroom farmer. Once passed, the floor of the tunnel is in very bad shape with areas completely washed away exposing the original 3 brick high water culvert with sandstone lids, running the entire length of the tunnel. Black walls are still present from years of loco soot, with the occasional chalk graffiti on the walls and some modern rubbish carelessly discarded on the tunnel floor. (Nothing compared to the mess left behind by the mushroom cultivators). The tunnels length is astounding and just goes on and on, dead straight till the light at the northern end is a small speck. You do notice the tremendous incline when walking up the tunnel (Stanwell Park to Otford). Towards the bend at end of the tunnel, the roof dramatically appears closer to you as the amount of erosion and earth run off has build up the area around the southern end. So much has washed down that the first manhole in from the southern end just pass the concrete brace, is at knee height. Environment & Heritage put the archaeology at 1.3m below current ground level at the southern end of the tunnel. Much graffiti and vandalism has occurred at the Stanwell Park (southern) end including the damage and removal of four layers of bricks on the left side of the portal which lined the tunnel and entrance.

The Otford Tunnel is truly a magnificent feat of engineering and hard work. The work involved just boggles ones mind when you consider man power made the bore and lined it with an artwork of bricks. Hats off to the gangers. Well done, even though the tunnel had a relatively short life of 32 years. Otford Tunnel celebrates its 125 year anniversary on the 3rd October 2013.

Update – by Ian Piggott – 20 January 2013 – originally appeared on http://helensburgh.wordpress.com/2011/01/04/otford-tunnel-tunnel-no-7-photo-update/ – 4 January 2011

I was fortunate enough to visit the Otford Tunnel again on the 27th December 2010. With all the recent rains I was keen to see if any erosion damaged had occurred to the tunnel floor as it is already in a very poor state. It had hardly suffered any ill affects from the rains at all , and not surprising as it has been there for 122 years.

It was great to walk through the tunnel again. What immediately sprung to mind was the sheer undertaking require to bore the tunnel and construct the elliptical brickwork. The central culvert (dish drain) running the entire length of the tunnel is still functional in most of the tunnel, with sandstone capping blocks mostly intact. What amazed me was to find a single plant growing in the eroded soil approximately 300m into the tunnel. I have no idea how it is photosynthesising, (see photo below).

What a sight it must have been to emerge from the Otford Tunnel southern portal to see the white sand of Stanwell Park beach and the entrance to the Illawarra. (The entire Stanwell Park amphitheatre was mostly cleared, especially during the deviation works). Oh how I wish the time machine were a reality. 🙂

The small town of Helensburgh in New South Wales is known as the gateway between the cities of Sydney and Wollongong, as it is located roughly halfway between the two (45km south of Sydney’s CBD and 34km north of Wollongong).

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